The invention relates to a foil element comprising a dielectric carrier layer and at least one electrically conductive layer arranged on the carrier layer, and to a method for producing such a foil element.
DE-B-102007030414 describes a method for producing an electrically conductive structure on a dielectric carrier substrate, such as a PET foil (PET=polyethylene terephthalate). In this case, firstly a conductive layer, a so-called seed layer, in the form of a conductor track, for example an RFID antenna, is formed by patterned printing of a conductive printing substance, for example metal particles bound in a dispersant, on the surface of the carrier substrate (RFID=Radio Frequency Identification). The printed seed layer is subsequently reinforced by plating in order to form the electrically conductive structure by means of a metallic coating being deposited on the conducive layer by the application of a current flow in an electrolyte containing a dissolved coating metal.
It is known that foil elements which are subjected to elevated temperatures, for example during a lamination process, can become wavy, which can result in considerable disadvantages. Thus, DE-A-102006029397 describes a plastic carrier foil with a security element arranged thereon, wherein the carrier foil, after a further plastic foil has been laminated over the carrier foil and after cooling of the layer composite, in the region of the security element, exhibits an orange peel effect in such a way that the security element appears wavy over its whole area. This problem is solved by heat treatment of the carrier foil before the security element is applied, since this evidently brings about a local reduction of the internal stress in the carrier foil.